True gums are formed from the
disintegration of internal plant tissues, mostly from the decomposition of
cellulose in a process called gummosis.Gums contain high amounts of sugar and are closely allied to the pectins.They are colloidal and soluble in water,
either dissolving entirely or swelling, but they are insoluble in alcohol and
ether.They exude naturally from the
stems or in response to wounding of the plant.Commercial gums arrive in the market in the form of dried
exudations.Gums are especially
common in plants of dry regions.They
are used primarily as adhesives, and are also used in printing and finishing
textiles, as a sizing for paper, in the paint and candy industries and as
drugs.Three important commercial
plant gums are gum arabic, gum tragacanth and karaya gum.

A dried gummy exudate obtained from Acacia senegal
and related acacias.These are small
native trees of arid northern Africa and are extensively cultivated in the
Sudan.The trees are tapped between
February and May when the fruits are ripe.Transverse incisions are made with a small ax and thin strips of the
outer bark are torn off.The gum slowly
exudes as a viscous liquid, collects in a drop and hardens.After 3-8 weeks these “tears” are
collected.The sun bleaches them, and
the impurities are removed before marketing.The Egyptians used gum arabic as early as 2,000 B.C.Sudan gum has been an article of commerce
since 100 A.D.Several kinds reach
world markets.Kordofan or Hashab gum
has been exported from the region around Cairo and Port Sudan, while Senegal
gum originates north of the Senegal River.Gum arabic is slowly and completely soluble in cold water and has a
high degree of adhesiveness and viscosity.Most has been used in textile, mucilage, paste, polish and
confectionery industries and as a glaze in painting.In medicine it has been used as an
emulsifying agent and as a demulcent.

This is formed by a transformation of the pith and
medullary-ray cells into a mucilaginous substance that exudes naturally or
after the bark has been punctured or excised.It comes from Astrangalus gummifer and other species of
that genus.They are thorny shrubs of
the arid regions of Western Asia and Southeaster Europe.The gum is allowed to dry on the bark
before it is collected.It reaches
the market in one of three forms:tears, which are the dried natural exudate; vermiform gum, which
consists of narrow twisted coils or strings; and flakes, which are ribbonlike
pieces.Most of the commercial supply
originates in Iran and Turkey.Gum
tragacanth has been used in calico printing and for other industrial purposes.It is one of the oldest drugs and was
known since 300 B.C.In modern medicine
it has served as an adhesive agent for pills and troches and for the
suspension of insoluble powders.

Karaya gum has been used as a substitute for gum
tragacanth, and several million pounds were imported annually from India by
the mid 1900’s.It is used in the
textile, cosmetic, cigar, past and ice cream industries.It is obtained from Sterculia urens,
a large tree in central India.Incisions are made into the heartwood and the gum oozes into these and
accumulates as large irregular knobs.They are then collected, sorted and graded.The gum enters the trade in the

Other Gums

There are many other plants, which produce gums of some
commercial importance.Gum ghatti,
obtained from Anogeissus latifolia, a large tree native to India and
Ceylon, is used as a substitute for gum arabic.The leaves are used for tanning.Feronia limonia and Cochlospermum religiosum in
India, Burma and Java yield gums that are also used in place of gum
arabic.The Asiatic Cycas
ciccinalis is the source of cycas gum.The carob, Ceratonia siliqua, produces tragasol, a mucilaginous
hemi cellulose occurring in the pods.Mesquite gum in North America is obtained fro Posopis juliflora,
P. glandulosa and other species, while cherry gum is found in various
species of Prunus.

Resins are formed as oxidation products of various essential oils and
are very complex and varied in chemical composition.The resin is usually secreted in definite cavities
or passages.It frequently oozes out
through the bark and hardens on exposure to air.Tapping is usually necessary in order to obtain a sufficient
amount to be of commercial value.Commercial resins are also frequently collected from fossil
material.Resinous substances may
occur alone or in combination with essential oils or gums.Resins, unlike gums, are insoluble in
water, but they dissolve in ether, alcohol and other solvents.Resin production is widespread in nature,
but only a few families are of commercial importance.These include the Anacardiaceae,
Burseraceae, Dipterocarpaceae, Guttiferae, Hammamelidaceae, Leguminosae,
Liliaceae, Pinaceae, Styracaceae and Umbelliferae.The exact botanical origin of a resin is often hard to trace,
especially in the case of fossil and semi fossil types.

Resins probably serve the plant by preventing decay,
which is due to their high antiseptic qualities.They may also lower the amount of water lost from the plant tissues.

Resins have certain characteristics that render them
important to industry.Their ability
to harden gradually, as the oil that they contain evaporates, makes possible
commercial varnishes.The resins are
dissolved in solvents and surfaces are painted with the mixture.As the solvents and oils evaporate, a thin
waterproof layer of resin remains.Resinous substances have been utilized for waterproof coatings, and
also for decorative coatings for millennia.Ancient Egyptians varnished their mummy cases and the utilization of
lacquer in the arts has been practiced in China and Japan for centuries.The Greeks and Romans were familiar with
many of the same resinous materials that are used today (e.g., mastic, amber,
sandarac).Another property of resins
that is of industrial importance is their ability to dissolve in alkalis to
form soap.Resins are also used in
medicine; for sizing paper; as a stiffening material for mats; in the
preparation of sealing wax, incense and perfumes; and for many other purposes
as well.

It is difficult to classify resins because the same
term is often used for very diverse materials.In commerce, resins are often referred to as gums, while such
terms as varnish resins, hard resins, spirit varnishes, balsams, gum resins,
damar resins, soft resins, and many others are used quite
indiscriminately.The chemical
differences between the various groups are much more definite.In this section three groups that will be
distinguished are Hard Resins, Oleoresins and Gum Resins.

These contain only a little if any essential oil.They are usually solid, quite transparent,
brittle substances with no particular odor or taste.They are readily fusible and burn in air
with a smoky flame.They are
nonvolatile and very poor conductors of electricity.They become negatively charged with
friction.The hard resins constitute
the best source of varnishes, due to their low oil content and the readiness
with which they dissolve in alcohol.The most important commercial resins, such as the copals and damars,
belong to this group.Hard resins are
also used in paints, inks, plastics, sizing, adhesives, fireworks and other
products.

Copals comprise a
considerable group of resins of recent, semi fossil and fossil origin that
are found in many tropical and subtropical areas of the world.The word “copal” is of Mexican
origin.Many of the harder copals are
called animes, especially in northern Europe.The copals insignificant quantities of oil and they yield a
hard elastic varnish, which has been widely used for outdoor work.Several types are know which are diverse
in character and source

Zanzibar copal and the closely related Madagascar and
Mozambique copals are derived from Trachylobium verrucosum.Zanzibar copal is the hardest of all resins
except amber and is very valuable.The resin exudes naturally from the trunk, branches and fruit.However, most of the commercial supply was
obtained from semi fossil material derived from still living trees, and
fossil material from trees that no longer exist.Fossil copal when removed from the ground is covered with a
crust of oxidized material.After
this has been removed, the copal shows a typical surface known as “goose
skin,” which consists of large and small excrescences.The interior is clear and transparent and
varies from yellow to brownish red in color.

Inhambane Copal is obtained from Copaifera conjugata,
a valuable timber tree in coastal Southeast Africa; but it is of little
commercial value.

There are a large number of hard resins among the West
African copals.They are usually
designated by the name of the region from which they were obtained.The most important of these are the Congo,
Angola, Sierra Leone, Acere and Benin copals.

Congo copal is the most important because it is very
hard and has been extensively exploited in the 20th Century.It is derived from Copaifera demeusii and
C. mapane, which are characteristic trees of the Congo Basin.Although living trees have furnished some
of the supply, the greater part was obtained from the ground or from
watercourses, and was more or less fossil in nature.The white and red Angola copals are
derived from the same two species.

Sierra Leone copal is a light-yellow, hard and brittle
resin that is obtained from Copaifera copallifera and C. salikounda.Live trees are wounded and the resin
exudes and hardens in the form of globular tears.Some fossil material is also obtained.Because of the value of this copal, the
Sierra Leone government has protected the trees.

Accra and Benin copals are probably derived from Daniella
ogea and related species.These
large trees are found in the coastal forests of Liberia, the Gold Coast and
Nigeria.The resinous exudation,
known locally as ogea gum, has gained prominence as a varnish resin.

This copal is one of the most valuable of the hard
resins.It is obtained from the kauri
pine, Agathis australis, which is the largest and most important tree
in New Zealand.The copal is chiefly
fossil in nature and is dug up on ridges and in swamps and bogs.“Swamp gum” furnishes the bulk of the
supply, and ranges in size from pieces that are 1-2 inches in diameter to
lumps weighing 100 lbs.“Range gum”
yields the best grade of kauri.Tapping living trees gets an inferior “Bush Gum”.Kauri is yellow, transparent and very
hard.It is an exceedingly valuable
varnish resin, especially for marine and outside work.It was also used in making linoleum.Kauri constituted one of the chief exports
of New Zealand in the mid 20th Century.

The first shipments of this important copal were made
from Manila and the name persisted, although by mid 20th Century 75 percent
of the product was shipped from Indonesia.The source of all the East Indian, Philippine and Malayan copals, of
which there are many different kinds, is Agathis alba.This is a tall conifer reaching a height
of 200 ft.The resin exudes
naturally, and is also obtained by systematic tapping.Some of the supply was derived from fossil
material and consisted of large, irregular, angular, milky pieces with a
yellowish interior.Hard, semi hard
and soft copals are included among the many different kinds in the
trade.Pontianak copal, a semi fossil
type from Borneo, is the hardest variety and was especially popular in the
United States.Manila copal varnishes
are durable, but they do not adhere strongly to surfaces and they are not
very brilliant.They are used chiefly
for interior work and enamels.These
copals are often erroneously called damars, although they are quite distinct
from the true damars.

The tall locust tree in South America, Hymenaea
courbaril, which is found in Brazil and other portions of Neotropical
America, is the main source of this copal.The stems, twigs and even the fruits exude a large amount of resin,
which trickles to the ground.The
commercial resin is collected from the base of living trees, and former trees
as well, and is marked as Demerara or Para Copal.It is the softest of all copals and therefore the least
valuable.

There is confusion in the term “damar.”The word is of Malayan origin and is used
by the natives to indicate a torch made of decayed wood and bark, mixed with
oil and powdered resin, wrapped in leaves and bound with strips of
rattan.At one time it did not refers
to any specific tree or resin.However, the word came to be a collective term for a great variety of
hard resins of different origin, and included even kauri and manila
copal.In the commercial trade the
term “damar” restricted to resins that re obtained from members of the
Dipterocarpaceae.A few resins from
species of the Burseraceae are also included.This distinction should be maintained for the true damars are
very different chemically from the various coniferous resins.Unlike Manila copal, damar is insoluble in
chloral hydrate, but completely soluble in alcohol and turpentine.

The trees that yield damars are characteristic of all
Southeastern Asia, and are particularly abundant in Malaya and Sumatra.Although all members of the Dipterocarpaceae
secrete resin, only a few species are of commercial importance.These are found mainly in the genera Balanocarpus,
Hopea and Shorea.Damars are especially important in Malaya and are obtained by tapping
the trees.The most important Malayan
varieties are Damar Mata Kuching from Hopea micrantha and related
species. Damar Penak from Balanocarpus heimii, and Damar Temak from Shorea
hypochra.The principal damars of
India are saldamar from Shorea robusta, white damar from Vateria
indica, and black damar from Canarium strictum.Damars also come from Borneo, Java,
Sumatra, Thailand and Cochin China. Batavian damar, a product of Shorea
wiesneri, is the best commercial variety.

The so-called East India resins are products of the
same trees that yield damars.They
are older and harder and are often gathered from the ground or from
watercourses.

Damars were used principally in spirit varnishes and
the manufacture of nitrocellulose lacquers.Damar varnishes adhere better than Manila copal varnishes, but are softer
and less durable.They are
particularly well adapted for varnishing paper because of their luster and
light color.They have also been used
for indoor work and in histology.

Amber is a fossil resin found mainly along the shore of
the Baltic Sea. and to a lesser extent in Mexico, Central America and
Caribbean Islands.The principal
source of Baltic amber was the now extinct pine, Pinus succinifera
that flourished on the shores of a former sea in the Eocene.Amber is very hard and brittle.It occurs in several forms, the most
important of which is succinite.Some
of these forms are transparent and others are almost opaque.The color varies from yellow to brown and
even black.Amber assumes a high
polish and becomes negatively charged when rubbed.It also gives off a characteristic aromatic odor.This substance has been known for
thousands of years.The Swiss Lake
Dwellers were familiar with it and it was highly prized by the Greeks and
Romans.It has always been used for
beads and other ornamental purposes and is often carved.

The chief use of amber is for the mouthpieces of pipes
and cigarette and cigar holders.The
darker grades yield a valuable varnish, but this is too costly for general
use.Amber is also used to increase
the elasticity of rayon fibers and as the source of an essential oil.It is of scientific interest that there
are often found imbedded in amber the remains of plants, insects and other
objects that existed at the time the fresh resin was exuded from the pine trees.

Lacquer is a natural varnish that exudes from various
trees in Asia, and great quantities of it are used in the Orient for
ornamental purposes.The principal
source is the lacquer tree, Rhus verniciflua, native to China but
cultivated in Japan.The trees are
systematically tapped.The exudate is
a milky liquid, which darkens and thickens rapidly on exposure to air.However, it can remain unchanged for long
periods by storage in closed containers.It is filtered before use.When applied as a varnish, the thin film rapidly hardens in a moist
atmosphere, in part due to oxidation.Lacquer impart5s a remarkable protection as it is unchanged by acids,
alkalis, and alcohol or heat up to 160 deg. Fahrenheit.Pigments may be mixed with the lacquer
before drying.

The lacquering process originated in China many
centuries before Christ, and reached its highest development during the Ming
dynasty (A.D. 1368-1644).In Japan
the first records are from the 4th Century, when lacquer was used for many
purposes.The earliest examples known
belong to the 6th Century.The art
reached its height during the 17th Century, although much fine work was produced
as late as the 19th Century.In Japan
the quality of lacquered goods is of the highest excellence.Gold has often been used as a
coloring.The process of lacquering
is very complicated and tedious.Sometimes 300-400 coats are applied and the whole operation requires
several years to complete.This
technique was kept secret for many years.

In Burma lacquer is obtained from Melanorrhoea
usitata.It dries more slowly
than Japanese lacquer, but has been used in an attempt to build an industry
in Burma.Natural lacquers are also obtained
in Taiwan and Vietnam, with Rhus succedanea being the source in the
latter.

True shellac is not a direct plant product but deserves
discussion here.It is made from
stick-lac, a resinous substance secreted on the twigs of many trees by an
insect, Tachardia lacca.The
lack insect derives its food from the sap of the trees and secretes the resin
as a kind of cocoon for its own protection and that of its offspring.Although there are about 40 species that
may serve as hosts for the insect, only seven are of importance.These are often cultivated.They include Butea monosperma,
Schleichera oleosa, Zizyphus xylopyrus, Ficus religiosa, Acacia nilotica,
Cajanus cajan, and Zizyphus jujuba.Butea monosperma was used as a host as early as 250 A.D.At first a valuable red dye, which was
obtained from the insect, was the only sought after product.However, since 1590 A.D. the resinous
excretions have been more important.Native workers prepare most of the shellac of industry.India furnished over 97 percent of the
total output by the mid 1950’s, the rest being from Burma, Thailand and
Vietnam.The crude stick-lac is
removed from the twigs and soaked in water to extract the red dye.It is then dried and powdered to a granular
consistency.This seed-lac is melted
and thin sheets of it are hardened.These are broken into the semitransparent, brittle, orange-red flakes
which make-up shellac.If the melted
seed-lac is poured out in droplets, it hardens into the thick round pieces
known as button-lac.Shellac is often
bleached.

At one time shellac had many industrial uses, but
synthetic substitutes made from petroleum have greatly competed with it.True shellac can be molded readily and was
the most satisfactory material for the manufacture of phonograph
records.It is an insulator of the
highest grade and was once extensively used in the electrical industry.It was the principal spirit-varnish resin
yielding a tough film with a smooth finish, which is also capable of a high
polish.Shellac varnishes cannot be
used out-of-doors because they are not water resistant.Shellac was also used in making sealing
wax, drawing inks, some watercolors and nitrocellulose lacquers; for sizing
papers; for stiffening felt hats; and, in India, for many ornamental
purposes.

These are grass-tree resins obtained from Australian
trees belonging to the genus Xanthorrhoea.These plants are among the few monocotyledons, other than
palms, which have an arboreal habit.They consist of a short woody stem, composed of the old leaf bases,
surmounted by a tuft of long rush like leaves.The resin collects around the bases of the old leaves and is
removed by beating the stem.The
yellow acaroid resins reach the market in the form of elongated or round
reddish-brown pieces.They are
obtained chiefly from Xxanthorrhoea hastilis.Red acaroid resins from X. tateana, X. australis,
and related species are much more common.They consist of uneven pieces of a brownish color.The acaroid resins are used in the
manufacture of sealing was, gold, size, and spirit varnishes for use in
coating metals; as a substitute for rosin in paper sizing and inks; as a
mahogany stain; as a source of picric acid; and in medicine.

This is a soft pale-yellow resin obtained mainly from
Tetraclinis articulata (= Callistris quadrivalis), a small tree
in Northern Africa.Australian
species of Callitris are also a source of sandarac.The resin is formed between the inner and
outer layers of the bark, and is excreted inn the form of small tears, which
quickly become opaque.Sandarac
yields a hard, white, rather brittle spirit varnish that is especially useful
for coating labels, negatives, cardboard, leather and metals.It was once used in medicine and was well
known to previous civilizations.

This is a very old resin that was known at least as far
back as 400 B.C.The most useful
variety is Chios mastic, derived from Pistacialenticus, a
small tree from the Mediterranean area.Although the resin exudes naturally, removing strips of bark enhances
the flow.Some of the resin adheres
to the trunk in the form of long, ovoid, pale-yellow, brittle tears, while
the remainder falls to the ground.Bombay mastic, which consists of large irregular pieces of a dull,
milky color, is from P. cabulica.Mastic yields a pale varnish used for coating metals and pictures,
both oils and watercolors.It is also
used in lithographic work, in perfumery, in medicine, and as cement for
dental work.It is one of the most
expensive and high-grade resins.

Included here are various deep red materials of a
resinous nature.Sumatra dragon’s
blood is from Daemonorops draco, a climbing rattan palm of Eastern
Asia.The dark reddish-brown resin
forms as small granules on scaly fruits.It is used mainly in the manufacture of red spirit varnishes for
metals and in making zinc line engravings.During the 18th Century Italian violinmakers used dragon’s blood in
their varnishes.Socotra dragon's
blood is a resin that exudes from the stem of Dracaena cinnabari of
Western Asia.It has been also used
for varnishes, dyes and stains.Dragon’s blood is sometimes secured from tropical American species of
Dracaena and other Asiatic species of Daemonorops.

Gum kinos are produced by several plant species.Malabar kino is derived from the dried
juice of Pterocarpus marsupium, a large tree in India.Trees are tapped and the juice is boiled
down.It reaches the market in the
form of small, brownish-red, brittle pieces.West African kino is a red resin from P. erinaceus.Bengal kino is from Butea monosperma.Some Australian species of Eucalyptus
are also sources of gum kino, but mainly Eucalyptus camaldulensis.The kino is secreted in cavities between
the wood and bark, and oozes out after incisions have been made.In the air the resin hardens into a solid
reddish mass.Several tropical
American trees, mainly Dipteryx odorata and Cocoloba uvifera, also yield
kinos.Kinos have found their main
use in medicine for throat disorders, and are sometimes used in tanning.

A considerable
amount of essential oils are contained in oleoresins in addition to the
resinous materials.Thus, they are
often liquid in nature.They have a
distinct aroma and flavor.Among the
oleoresins we find the turpentines, balsams and elemis.There is only a very slight distinction
between these groups and often a confusion of names.

These are oleoresins
that are obtained almost exclusively from coniferous trees.They are viscous, honey like liquids or
soft and brittle solids.The resin is
secreted and stored in ducts near the cambium layer and exudes naturally as a
soft, sticky substance, often called pitch.For commercial use crude turpentine is obtained by tapping the
trees.On distillation turpentines
yield the essential oil or spirits of turpentine, and rosin, both of which
are useful products around which an important industry had been built in the
20th Century.The turpentine or
navel-stores industry was one of the oldest of the forest industries.The Trojans and Greeks were familiar with
pitch and its uses, and it is mentioned in the Bible.The industry was valued at 35-40 million
US dollars annually by the mid 20th Century.The United States led in production with over half of the total
output.Turpentine and rosin are also
produced in Europe and India and Vietnam.

Turpentines from
various species of conifers have been frequently used in their natural state
for purposes other than the production of naval stores.Some of them have been important in
industry, in the arts and particularly in medicine for over five
centuries.Among the more common are
the following:

This is actually turpentine rather than a balsam, as
the name seems to indicate.It is
secreted by the balsam fir, Abies balsamea, of northeastern North
America.The resin collects in
elongated blisters on the bark and only small amounts are obtainable.It was estimated that a tree could yield
from 8-10 oz. per year.Collectors
use a pot with a spout cut at an angle.This is forced into the blisters and held in place while the balsam
drains out.The balsam is a viscid
yellowish or greenish substance.It
main use has been as a mounting medium for microscopic work and as cement for
optical lenses.It is very
transparent and has a high refractive index, which results in a minimum of
dispersed light.The medicinal value
of Canada balsam was known as early as 1607.It was used as an irritant, stimulant and antiseptic, and is a
component of collodion and some plasters.It has also been used as a fixative for soap and perfumes.

Oregon Balsam is obtained from the Douglas fir and it
has similar properties and uses.

This is the natural exudation
of various species of spruce of North America, with Picea rubens being
the main source.It is usually the
result of an injury to the sapwood.The thin, clear, bitter, sticky oleoresin is secreted in blister like
cavities in the bark or in longitudinal fissures in the wood.It hardens on exposure to the air and is
collected when hard or semi soft.Before the advent of chewing gum about 500,000 lb. were used each year
as a substitute.The gum softens in
the mouth and assumes a reddish color.It has a pleasing resinous taste.

This turpentine is obtained from the European larch, Larix
decidua, a widespread tree in the mountains of Central Europe.Unlike other conifers, the resin ducts are
located in the heart of the tree so that holes are bored in order to obtain
the resin.The trees are tapped in
the spring.Venetian turpentine has
been an important product since the middle of the 18th Century.It is a yellowish or greenish liquid with
a typical odor and taste.It has been
used in varnishes, histology, lithographic work and veterinary medicine.

Turpentines of small importance include Bordeaux
turpentine from Pinus pinaster, Strasbourg turpentine from Abies
alba and Jura turpentine from Picea abies.In he first two of these European
turpentines, the crude exudation is used to some extent, but generally it is
strained and filtered through cloth.The residue, known as Burgundy pitch, is a stimulant and
counterirritant, and has been used in plasters, ointments and other
pharmaceutical preparations.

These are
technically oleoresins that contain benzole or cinnamic acid and therefore
are highly aromatic.However, the
term “balsam” is frequently applied in error to much different substances,
such as Canada balsam, copaiba balsam, etc.The true balsams contain much less oil than the turpentines and are
more viscous.They yield essential
oils on distillation. Balsams are
used in medicines and as fixatives in the perfume industry.

This balsam is from Myroxylon pereirae, a tall
tree in Central America.It is
cultivated in many tropical and subtropical areas.The wood resembles mahogany and is valuable.The balsam is a dark, reddish-brown,
thick, syrupy, viscous liquid, and is a pathological product formed as a
result of wounding the tree.The tree
trunks are beaten with a blunt instrument and the injured bark is then
charred.It falls off naturally or is
removed.Sometimes small “windows”
are cut in the bark.The balsam
exudes from the exposed surface of the wood and is collected on cloths.These cloths are later boiled to free the
purified balsam.Balsam of Peru has
been used in medicine for healing wounds and skin diseases.During World War II it was used in field
dressings for quick applications of a protective covering to the surface of
wounds.It has also been used in the
treatment of coughs, bronchitis and similar ailments, because of its
simulative and antiseptic effect on the mucous membranes.It is utilized in perfumes as a fixative
for the heavier odors and has served as a substitute for vanilla.Its common name is a misnomer because the
tree does not grow in Peru.The main
supply for the United States has been El Salvador.

This balsam is a pathological product obtained from Myroxylon
balsamum, a tree of Venezuela, Colombia and Peru.Incisions with a V-shape are made in the
trunk and the balsam exudes slowly and is collected in gourds.It is a brown or yellowish-brown plastic
substance with a pleasant aromatic taste and odor.It has been used for salves and ointments and as an expectorant
and antiseptic in the treatment of coughs, colds and bronchitis.It is sometimes used to flavor cough
syrups.Considerable amounts have
been used as fixatives in the perfume and soap industries.

Styrax, or storax, occurs in two forms.The most important type, the styrax of
antiquity, is known as Levant styrax.This is obtained from Liquidambar orientalis, a small tree
found along the coasts of southwestern Asia Minor.The balsam issues as a pathological product from a wound.The outer bark is bruised and soon the
balsam exudes into the inner bark.The outer layers are discarded and the balsam is recovered by boiling
the inner layers in seawater.The
residual bark is dried and used for fumigation.Styrax is a semi liquid, grayish-brown, sticky, opaque
substance with a pronounced aromatic odor.It has been used in soaps and cosmetics; as a fixative for the heavy
oriental type of perfume; in adhesives, lacquers, and incense; as a flavoring
for tobacco; and in medicine as a stimulant to the mucous membranes and for
the treatment of scabies.

American styrax is obtained from the sweet gum, Liquidambar
styraciflua.

This is a solid balsam that is often classified as a
resin or balsamic resin.It is the
pathological product obtained from several species of Styrax in
Southeastern Asia and the East Indies.The balsam oozes from incisions made in the trunk and branches.Two varieties are known in commerce.Siam benzoin is from Styrax tonkinense and
S. benzoides and occurs as yellowish or brownish pebble like tears
with a milky white center.The tears
are hard and brittle at room temperature and occur separately or adhere
together slightly.Sumatra benzoin,
from Styrax benzoin, occurs in reddish or grayish-brown blocks or lumps,
composed of masses of tears stuck together.Benzoin is exceedingly aromatic with a vanilla like odor.It is used in medicine as a stimulant and
expectorant; and in the preparation of heavy sweet perfumes, soap, toilet
waters, lotions, tooth powders, incense and fumigating materials.

Also known as copaiba balsam or copaiba, this product
is a natural oleoresin obtained from several species of Copaifera from
tropical South America.The copaiba
trees are small with strong, tough, durable wood, which contains resin ducts
of a large size.So much oleoresin is
secreted and stored in cavities that sometimes the pressure causes the trunks
to burst.Copaiba is obtained by
boring holes into the heartwood.The
secretion flows out very rapidly.It
is a thin, clear, colorless liquid at first, but turns yellow and becomes
more viscid with age.It has a
peculiar aromatic odor and a persistent bitter taste.Several commercial varieties occur, which
differ in the amount of resins and essential oils present as well as inn the
source.The most important are
Maracaibo copaiba from Venezuela, obtained from Copaifera officinalis,
which contains much resin and is rather thick; and Para copaiba, a very fine
grade from Brazil, obtained from C. reticulata.Copaiba has been used in making varnishes,
lacquers, and tracing paper, as a fixative in scenting soaps and perfumes,
and in photography to emphasize half tones and shadows.In medicine it was used as a disinfectant,
laxative, diuretic, and mild stimulant.Amerindians used it for its healing properties.It became known in Europe early in the
16th Century.

Substitutes for copaiba are Gurjun Balsam and Illurin
Balsam.

Gurjun Balsam is obtained from Dipterocarpus
turbinatus and related species from India and the East Indies.The thick, opaque, grayish oleoresin is
obtained by cutting holes in the trunk.

Illurin Balsam or African Copaiba is a very fragrant
oleoresin with a thick pungent, pepperlike odor that originates from a West
African tree, Daniella thurifera.This species is sometimes called Sierra Leone Frankincense.It is found in the drier open forests and
savannahs of Upper Guinea.The resin
exudes in a copious flow from the base of the trees.A similar product comes from D. oliveri,
a species of the denser moist forests.This oleoresin, under the name of wood oil, was once one of the chief
products of Nigeria.

This name is used as a collective for several
oleoresins of different origin.It is
also used in error as a synonym for some of the soft copals.Elemis differ considerably in their
characteristics.These oleoresins
exude as clear pale liquids, but they tend to harden on exposure.Some remain soft, while others become very
hard.

Manila Elemi is the most important and the best know of
the elemis.Its source is the pili
tree, Canarium luzonicum, of the Philippines.The oleoresin is secreted in the bark and
oozes from the trunk in fragrant white masses.Native people have used elemi for torches and for caulking
their boats.Manila elemi has been
used in lithographic work and in the manufacture of inks, adhesives, and
cements; in the varnish industry to give toughness and elasticity to the
products; in perfumes; and in medicine in plasters and ointments.

Of lesser importance is
African Elemi from Boswellia frereana; Mexican Elemi from Amyris
elemifera, A. balsamifera and other species; and Brazilian Elemi
from Protium heptaphyllum, Bursera gummifera and other trees.

This is a greenish turbid oleoresin with the odor of
rosemary.It is obtained from
Commiphora opobalsamum, in Arabia.This material has long been used in incense and for perfumes of an
oriental type.It has some medicinal
value.The supply of Mecca balsam has
always been limited and thus is a rare and costly product.

Gum resins are
mixtures of both true gums and resins and naturally combine the traits of
both groups.They often contain small
amounts of essential oils and traces of coloring material.Gum resins occur naturally as milky
exudates and collect in the form of tears or irregular masses.Injuring or tapping the plants also
produces them.They are mostly from
plants of dry, arid regions, especially species of the Umbelliferae and
Burseraceae.Three of the
umbelliferous species, the sources of ammoniacum, asafetida and galbanum, are
very common in Iran and Afghanistan and furnish the characteristic aspects of
the vegetation of the plains and steppes in those regions.During the dry season these plains are
barren, but shortly after the rains begin, these plants send up thick stems
from their perennial rootstalks.When
fully grown the plants attain a height of 5-6 ft., and are so abundant that
they from a kind of open forest.

This is obtained from Dorema ammonniacum, a
tall, stout naked, hollow-stemmed perennial found in the deserts of Iran,
southern Siberia and other parts of Western Asia.It has a milky juice, which exudes from the stem and flowering
branches and hardens into tears.Insect injury often causes the exudation to occur.The brownish-yellow tears are hard and
brittle and occur singly or in masses.Ammoniacum is used in medicine as a circulatory stimulant, and in
perfumery.

This is derived from
Ferula assafoetida and allied species, stout perennial herbs of Iran and
Afghanistan.The cortex of the thick
fleshy roots exudes a milky juice during the rainy season.The crown of the roots is cut off and
protected from the sun.The gum resin
gradually collects on the surface in the form of tears, or masses of tears of
varying colors imbedded in a thick, gummy, grayish or reddish matrix.Asafetida has a powerful and foul odor and
a bitter acrid taste, due to sulfur compounds present in the essential
oil.Despite this it has been used
throughout the East for flavoring sauces, curries and other foods, and as a
drug.In Europe and America is used
in perfumes and for flavoring only when exceedingly dilute and after certain
impurities have been removed.Asafetida has may valuable medicinal properties and is used in the
treatment of coughs, asthma, and other nervous disorders and as an aid to
digestion and metabolism.

Galbanum is a gum resin excreted from the lower part of
the stems of Ferula galbaniflua, a stout herbaceous perennial of
Northwestern Asia.It occurs in the
form of separate tears or brownish and yellowish-green masses.It has been used for centuries in
medicine.Galbanum has a powerful
tenacious aromatic odor.

This is one of the oldest and most valuable of the gum
resins.There has been some confusion
regarding its source because two forms seem to occur.

Herabol Myrrh is derived from Commiphora myrrha,
a large shrub or small tree of Ethiopia, Somaliland and Arabia.The gum resin oozes naturally from the
stems or as a result of wounding.The
pale-yellow liquid gradually solidifies and becomes brown or even black in
color.Herabol myrrh is used in
perfume manufacture and for medicinal purposes as a tonic, stimulant, and
antiseptic and is often a constituent of mouthwashes and dentifrices.

Bisabol Myrrh or Sweet Myrrh is from Commiphora
erythraea, and Arabian species of similar appearance.This is the myrrh of antiquity and has
been used for centuries in incense, perfumes and embalming.Myrrh was an important product in Biblical
times, ranking with gold in value.It
is still used in perfumes and incense for religious ceremonies.It is one of the constituents of Chinese
joss sticks.

This is also known as Olibanum and is obtained from Boswellia
carteri and related Asiatic and African species.The clear yellow resin exudes from
incisions made in the bark and hardens as small yellow grains.Frankincense, like myrrh, has been a
valuable material since Biblical times.It is still an indispensable ingredient of incense for religious
purposes, and is also used in perfumes, because of its excellent fixative
properties, face powders, pastilles and fumigating powders.

These gum resins have been of much less
importance.Opopanax is derived from
two very distinct plants, Commiphora kataf of the Burseraceae and Opopanax
chironium of the Umbelliferae.It
is used in perfumery and was formerly of importance in medicine.

Bdellium is a bitter aromatic gum resin obtained from Commiphora
mukul of India and C. africana of Africa.It has been used in the perfume industry.

There are other resinous substances, which find no use
in industry but are treated under “Medicinal Plants.”These include aloes, guaiacum, jalap and podophyllum,
and will be treated later.Gamboge, a
gum resin is discussed under “Dye Plants.”